Hillary Clinton is expected Sunday to formally announce her intention to run for president in the 2016 election.

The former secretary of state will announce her campaign for the Democratic Party's presidential nomination² with an online video posted on social media, sources familiar with her plans told media outlets³. They said she will then make stops in key early voting states, including Iowa and New Hampshire.

It will be Clinton's second presidential bid after her failed effort in 2008, when Barack Obama won the party's nomination on his way to becoming president. Clinton is considered a huge favorite to win the Democrats⁴' nomination this time.

A recent Gallup poll found 48 percent of those surveyed have a favorable impression of Clinton, her lowest rating since 2008. Forty-two percent of those polled had an unfavorable rating of her.

If elected, the former first lady would be the nation's first female president.

On the Republican side, Senators Ted¹ Cruz and Rand Paul have announced their intention to run for their party's nomination, and Senator Marco Rubio is widely expected to join them on Monday. Others expected to join what analysts⁵ say will be a crowded Republican field include former Florida governor Jeb Bush and Wisconsin Governor Scott Walker.

前美国国务卿希拉里.克林顿预计星期天正式宣布她计划在2016年选举中竞选总统。了解克林顿计划的人士对媒体说，克林顿计划通过社交媒体发布视频，宣布竞争民主党的总统候选人提名。消息人士说，克林顿随后将前往包括爱荷华和新罕布什尔等最早举行初选的州。

这将是克林顿2008年竞争民主党提名失利后的再次竞选努力。奥巴马赢得了民主党提名，并赢得大选，入主白宫。克林顿这次被非常看好将赢得民主党的提名。

一项最近的盖洛普民意调查显示，受访者中48%的人对克林顿印象良好。这是她2008年以来最低的支持率。42%的受访者不看好克林顿。如果这次当选总统，克林顿将成为美国第一位女性总统。

共和党籍的两位参议员，科鲁兹和保罗已经宣布将角逐共和党的总统候选人提名。广泛预计，卢比奥参议员星期一将宣布参选。预计将有多名共和党人加入竞争总统提名人的行列，包括前佛罗里达州长杰布.布什和威斯康辛州长沃克。